It’s no secret that Lockheed Martin’s F-35C naval variant has been plagued by cost overruns and setbacks throughout it’s production, but now it seems Boeing, Lockheed’s main rival, smells blood in the water and is capitalizing on the aircraft’s troubles.

The F-35C promised to revolutionize carrier aircraft by becoming the first stealth plane to launch from catapults at sea, but as production lags and costs rise, even President Donald Trump took notice, calling the program “out of control” and ordering a review of the costs and capabilities compared to Boeing’s latest offering.

As Dan Gillian, Boeing’s vice president of F/A-18 and EA-18 programs told Business Insider in January, the defense giant has been working on an update to the F/A-18 for years, and he thinks it could cover a significant portion of the F-35C’s job on cost and on schedule.

Boeing has proposed what it’s calling the F/A-18 Advanced Super Hornet, an update on the carrier aircraft that has served the Navy for decades. Meanwhile, F-35 advocates swear that no matter how you modify an F/A-18, it will still lack one essential ingredient that makes the F-35 so revolutionary — stealth.